Analytical examples of reversal current, zero core current, and surface current, toroidal magnetostatic equilibria with nested flux surfaces
- AIM, Unite Mixte de Recherche CEA - UP7 - CNRS, UMR no. 7158, Centre d'Etudes de Saclay, F-91191 Gif-sur-Yvette Cedex (France)
We present exact analytical examples of three types of axisymmetric toroidal magnetostatic equilibria with nested flux surfaces: (1) current reversal equilibria, for which the net toroidal current switches from a negative to a positive value when moving away from the magnetic axis; these equilibria have a non-monotonic pressure profile, in accordance with Hammett et al.'s theorem stating that the pressure on the current reversal surface has to exceed the volume-averaged pressure within that surface; (2) zero core current equilibria, in which the toroidal current density vanishes inside some flux surface; and (3) surface current equilibria, constituted of an arbitrary number of nested layers inside which the plasma pressure is constant and the magnetic field force-free, with two adjacent layers being separated by a current sheet. All these configurations are obtained by shaping in an adequate way the arbitrary function which intervenes in the class of generalized isodynamic equilibria first constructed by Palumbo and recovered later on by Bishop and Taylor. A derivation of these equilibria by a method slightly different from Palumbo's is given in an Appendix.
- OSTI ID:
- 22072580
- Journal Information:
- Physics of Plasmas, Vol. 19, Issue 7; Other Information: (c) 2012 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 1070-664X
- Country of Publication:
- United States
- Language:
- English
Similar Records
Topology of tokamak plasma equilibria with toroidal current reversal
Hamiltonian approach to the magnetostatic equilibrium problem